Protein Kinase C-Induced Early Growth Response Protein-1 Binding to SNAIL Promoter in Epithelial–Mesenchymal Transition of Human Embryonic Stem Cells

Abstract

Epithelial-mesenchymal transition (EMT) has been thought to occur during early embryogenesis, and also the differentiation process of human embryonic stem (hES) cells. Spontaneous differentiation is sometimes observed at the peripheral of the hES cell colonies in conventional culture conditions, indicating that EMT occurs in hES cell culture. However, the triggering mechanism of EMT is not yet fully understood. The balance between self-renewal and differentiation of human pluripotent stem (hPS) cells is controlled by various signal pathways, including the fibroblast growth factor (FGF)-2. However, FGF-2 has a complex role for self-renewal of hES cells. FGF-2 activates phosphatidylinositol-3 kinase/AKT, mitogen-activated protein kinase/extracellular signal-regulated kinase-1/2 kinase, and also protein kinase C (PKC). Here, we showed that a PKC rapidly induced an early growth response protein-1 (EGR-1) in hES cells, which was followed by upregulation of EMTrelated genes. Before the induction of EMT-related genes, EGR-1 was translocated into the nucleus, and then bound directly to the promoter region of SNAIL, which is a master regulator of EMT. SNAIL expression was attenuated by knockdown of EGR-1, but upregulated by ectopic expression of EGR-1. EGR-1 as the downstream signal of PKC might play a key role in EMT initiation during early differentiation of hES cells. This study would lead to a more robust understanding of the mechanisms underlying the balance between selfrenewal and initiation of differentiation in hPS cells.

The Trans-Spliced Long Noncoding RNA tsRMST Impedes Human Embryonic Stem Cell Differentiation Through WNT5A-Mediated Inhibition of the Epithelial-to-Mesenchymal Transition

“…The EMT process has been described under various hESC differentiation conditions, and its association with the differentiation of hESCs has also been confirmed . EMT of hESCs involves the E‐to‐M morphological conversion and marker expression change.…”

“…While we demonstrated that WNT5A contributes to in vitro differentiation of hESCs, the precise route by which WNT5A regulates hESC differentiation remains to be defined. Our results raise two possibilities: (i) WNT5A may directly target and down‐regulate the pluripotency regulatory circuit of hESC or (ii) it may directly activate differentiation pathways, such as the EMT pathway to augment the intensity of in vitro differentiation (Fig. ).…”

A Simple Method for Labeling Human Embryonic Stem Cells Destined to Lose Undifferentiated Potency

“…To define the relationship between JC‐1 intensity and cell differentiation status, H9 cells were stained with anti‐vimentin (an early differentiation maker [15, 20]) and anti‐OCT‐3/4 (a differentiation maker [13]). The JC‐1 signals were highly overlapped with those of vimentin (Fig.…”

Prediction of Differentiation Tendency Toward Hepatocytes from Gene Expression in Undifferentiated Human Pluripotent Stem Cells

“…Immunocytochemistry was performed as described previously [56,57]. The primary and secondary antibodies used in this study are listed in Supplementary Table S2.…”